Vehicle trucks and cars for pulling trailers commonly use what is known as a west-coast type rear view mirror assembly which includes an elongated mirror that is mounted on extended arms to stand out and away from the vehicle body. These mirrors are of such length that they usually do not require adjustment of the vertical viewing angle, once they are set, but different trailers lengths, different drivers, and different driver positions do make it desirable to be able to adjust their side viewing angle.
Although remote control rear view mirror operators are known for other uses, they are not adaptable for use with this type of mirror.
Since this type of truck mirror stands out some distance from the vehicle, and is of an appreciable size, it is very subject to wind deflections when the vehicle truck or car is traveling at any appreciable speed. Accordingly, it must be relatively fixed and held in any given readjusted position and this normally requires manual adjustment, outside the vehicle and when the vehicle is at rest.
Cable control operators require a certain freedom of movement as regards the mirror which precludes their use unless the mirror is within a protective wind shroud. Other types of actuators are impractical for like reasons of stiffness required in the mirror mounts and because of the removed location of the mirror so far out and away from the vehicle body. Even electrical control devices have been unsatisfactory because of gear train play and the size of the unit required to be hung on the mirror assembly.
The cost of a remote control rear view operator for truck mirrors is also a very important consideration. These mirrors are frequently damaged, since they stand out so far from the vehicles on which mounted, and any control device that is mounted on them must be relatively inexpensive to produce and to install. It must also be relatively small and compact in size, since it will also afford a certain amount of wind resistance, and can otherwise contribute to wind deflection and other problems.
Although various types of remote control operating mechanisms are known for use with rear view mirrors, a really acceptable remotely controlled operator for truck mirrors requires a unique combination of engineering and manufacturing talents to produce the relatively inexpensive and highly serviceable end product that is needed.